1. Field of the Invention
The present invention relates to USB connectors and more particularly, to such a USB connector, which has a rear cover fastened to the rear side of the first connection port and the top side of the bottom positioning member to shield the first and second conducting terminals, the adapter terminals and the circuit module, prohibiting them from contacting the outer metal shield to cause a short circuit.
2. Description of the Related Art
Following fast development of modern electronic technology, many different advanced and small-sized electronic devices have been intensively used in our daily life. Nowadays, many people use notebook computer instead of desk computer for the advantage of high mobility. Further, different interface devices shall be used for data and/or signal transmission between a host and different peripheral apparatus, or among different electronic devices. USB (Universal Serial Bus) interface devices are most popularly used interface devices for the advantage of hot-plug capabilities.
An early design of USB 2.0 standard (USB Hi-Speed) improves the transmission speed from 12 Mbps up to 480 Mbps. However, this design can simply be used in a peripheral apparatus (such as card reader, printer, memory stick, network phone, and network camera) of low driving power. Nowadays, these data transmission speeds cannot satisfy the demand for quick transmission of a big amount of data within a limited time, i.e., USB2.0 cannot be used with a high capacity hard disk drive or DVD copier, DVD player or any advanced blue light electronic device. In consequence, high speed data transmission connectors have been continuously created. For example, USB 3.0 standard (USB Super-Speed) provides a transmission speed as high as 4.8 Gbps. In consideration of compatibility to conventional USB 2.0, USB 3.0 maintains the original conducting terminals and adds an extra set of conducting terminals, i.e. a USB 3.0 connector has two sets of conducting terminals arranged therein to support two-way transmission at a high speed. The enhanced power supplying capability of USB 3.0 standard allows the use of a detachable high-capacity hard disk drive without extra power supply, and also permits connection of extra peripheral apparatus.
FIG. 14 illustrates a conventional USB 2.0 multi-port connector. According to this design, the USB 2.0 multi-port connector comprises a connector body A, an upper row of conducting terminals B, a bottom row of conducting terminals C and a metal shield D. The connector body A defines therein a first connection port A1 and a second connection port A2. The upper row of conducting terminals B and the bottom row of conducting terminals C are respectively mounted in the first connection port A1 and second connection port A2 of the connector body A. The conducting terminals B;C each have a signal input end B1;C1 extended out of the connector body A and bonded to an external circuit board, and a signal output end B2;C2 suspending in the first connection port A1 or second connection port A2 at the bottom side. The metal shielding shell C surrounds the connector body A, comprising a front shell D1, a back shell D2 and a middle clamping plate D3. The front shell D1, the back shell D2 and the middle clamping plate D3 are assembled together for grounding and electromagnetic protection. During application, the first connection port A1 and second connection port A2 of the connector body A can receive a respective external USB 2.0 connector for signal transmission between electronic apparatus.
Based on the design of the aforesaid USB2.0 female connector, extra conducting terminals may be installed in the connector body A to constitute a USB3.0 female connector. However, due to limited internal space, it is difficult to install an extra row of conducting terminals in the connector body A. Further, when a big number of conducting terminals are installed in the connector body A, signal transmission interference may occur, lowering the signal transmission quality and increasing the risk of electromagnetic interference. Further, after installation, the upper row of conducting terminals B and the bottom row of conducting terminals C may touch the metal shield D accidentally, causing a short circuit and increasing product defective rate.
Therefore, it is desirable to provide a USB connector, which eliminates the drawbacks of conventional USB2.0 multi-port connectors.